Lamp strings have been widely used in festival and holidays for decoration and celebration purposes. Conventional lamp strings are comprised of a pair of electrical wires and lamp strings connected to the wires in series or parallel. Each lamp string comprises a plurality of lamp bulbs. To effect flashing, a primary bulb is connected to each lamp string and the primary bulb comprises a bimetal switch, which opens and closes the circuit of the bulb due to high temperature caused by the current flow through the bimetal switch. This causes flashing of the lamps.
The flashing of such a conventional arrangement is fixed. In other words, variation of the lighting operation of the lamps is not available for such an arrangement. Further, the electrical characteristics of each primary bulb are unique, which makes the plurality of lamp strings lit in different timing. No precise control of the lighting timing can be realized.
Another conventional technique employs a controller to control the lighting operation of the plurality of lamp strings. The controller reduces a sequential control signal that controls the lighting of the lamp strings individually. In addition, the controller is provided with different lighting schemes, which can be selected by a user through a user-operating knob or switch. Thus, the lighting operations of the plurality of lamp strings can be selectively different from each other and variation of the lighting of the lamp strings can be realized.
The use of controller effectively improves the control of lighting of the lamp strings. However, it is manually operated. The user must manually operate the knob to switch between different lighting schemes. In addition, although several different lighting schemes are provided in advance, addition or modification of these preset lighting schemes cannot be realized through the conventional technique.
Thus, the present invention is aimed to provide a control technique, which provides, for lighting lamp strings, flexibility in variation of the lighting schemes and modes without manual switching operation.